Manipulation of metavalent bonding to stabilize metastable phase: A strategy for enhancing zT in GeSe

Abstract

Exploration of metastable phases holds profound implications for functional materials. Herein, we engineer the metastable phase to enhance the thermoelectric performance of germanium selenide (GeSe) through tailoring the chemical bonding mechanism. Initially, AgInTe₂ alloying fosters a transition from stable orthorhombic to metastable rhombohedral phase in GeSe by sbstantially promoting p-state electron bonding to form metavalent bonding (MVB). Besides, extra Pb is employed to prevent a transition into a stable hexagonal phase at elevated temperatures by moderately enhancing the degree of MVB. The stabilization of the metastable rhombohedral phase generates an optimized bandgap, sharpened valence band edge, and stimulative band convergence compared to stable phases. This leads to decent carrier concentration, improved carrier mobility, and enhanced density-of-state effective mass, culminating in a superior power factor. Moreover, lattice thermal conductivity is suppressed by pronounced lattice anharmonicity, low sound velocity, and strong phonon scattering induced by multiple defects. Consequently, a maximum zT of 1.0 at 773 K is achieved in (Ge_0.98Pb_0.02Se)_0.875(AgInTe₂)_0.125, resulting in a maximum energy conversion efficiency of 4.90% under the temperature difference of 500 K. This work underscores the significance of regulating MVB to stabilize metastable phases in chalcogenides.

Keywords

band structure / GeSe / metastable phase / metavalent bonding / thermoelectric

References

[1] Xiao T, Nagaoka Y, Wang X, et al. Nanocrystals with metastable high-pressure phases under ambient conditions. Science. 2022;377(6608):870-874.

[2] Ostwald W. Lehrbuch der allgemeinen chemie. Wilhelm Engelman;1893.

[3] Palumbo M, Battezzati L. Thermodynamics and kinetics of metallic amorphous phases in the framework of the CALPHAD approach. Calphad. 2008;32(2):295-314.

[4] Tan X, Geng S, Ji Y, et al. Closest packing polymorphism interfaced metastable transition metal for efficient hydrogen evolution. Adv Mater. 2020;32(40):2002857.

[5] Bundy FP. The P, T phase and reaction diagram for elemental carbon, 1979. J Geophys Res Solid Earth. 1980;85(B12):6930-6936.

[6] Zhao W, Pan J, Fang Y, et al. Metastable MoS₂: crystal structure, electronic band structure, synthetic approach and intriguing physical properties. Chem Eur J. 2018;24(60):15942-15954.

[7] He J, Tritt TM. Advances in thermoelectric materials research: looking back and moving forward. Science. 2017;357(6358):eaak9997.

[8] Zhu T, Liu Y, Fu C, Heremans JP, Snyder JG, Zhao X. Compromise and synergy in high-efficiency thermoelectric materials. Adv Mater. 2017;29(14):1605884.

[9] Li P, Qiu P, Xu Q, et al. Colossal nernst power factor in topological semimetal NbSb₂. Nat Commun. 2022;13(1):7612.

[10] Jiang B, Yu Y, Cui J, et al. High-entropy-stabilized chalcogenides with high thermoelectric performance. Science. 2021;371(6531):830-834.

[11] Fan Y, Xie C, Li J, et al. Engineering thermoelectric performance of α-GeTe by ferroelectric distortion. Energy Environ Mater. 2022;7(2):e12535.

[12] Liu Z, Hong T, Xu L, et al. Lattice expansion enables interstitial doping to achieve a high average zT in n-type PbS. Interdiscip Mater. 2023;2(1):161-170.

[13] He R, Schierning G, Nielsch K. Thermoelectric devices: a review of devices, architectures, and contact optimization. Adv Mater Technol. 2018;3(4):1700256.

[14] Yang D, Xing Y, Wang J, et al. Multifactor roadmap for designing low-power-consumed micro thermoelectric thermostats in a closed-loop integrated 5G optical module. Interdiscip Mater. 2024;3(2):326-337.

[15] Xie H, Zhao L-D, Kanatzidis MG. Lattice dynamics and thermoelectric properties of diamondoid materials. Interdiscip Mater. 2024;3(1):5-28.

[16] Zhang W, Lou Y, Dong H, et al. Phase-engineered high-entropy metastable fcc Cu_2–yAg_y(In_xSn_1–x)Se₂S nanomaterials with high thermoelectric performance. Chem Sci. 2022;13(35):10461-10471.

[17] Pei J, Cai B, Zhuang H-L, Li J-F. Bi₂Te₃-based applied thermoelectric materials: research advances and new challenges. Natl Sci Rev. 2020;7(12):1856-1858.

[18] Shi H, Su L, Bai S, et al. Realizing high in-plane carrier mobility in n-type SnSe crystals through deformation potential modification. Energy Environ Sci. 2023;16(7):3128-3136.

[19] Zhu Y-K, Jin Y, Zhu J, et al. Design of n-type textured Bi₂Te₃ with robust mechanical properties for thermoelectric micro-refrigeration application. Adv Sci. 2023;10(6):2206395.

[20] Tang X, Li Z, Liu W, Zhang Q, Uher C. A comprehensive review on Bi₂Te₃-based thin films: thermoelectrics and beyond. Interdiscip Mater. 2022;1(1):88-115.

[21] Wei T-R, Qiu P, Zhao K, Shi X, Chen L. Ag₂Q-based (Q = S, Se, Te) silver chalcogenide thermoelectric materials. Adv Mater. 2023;35(1):2110236.

[22] Tang Y, Yu Y, Zhao N, et al. High-performance thermoelectric α-Ag₉Ga_1–xTe₆ compounds with ultralow lattice thermal conductivity originating from Ag₉Te₂ motifs. Angew Chem Int Ed. 2022;61(36):e202208281.

[23] Hu L, Luo Y, Fang Y-W, et al. High thermoelectric performance through crystal symmetry enhancement in triply doped diamondoid compound Cu₂SnSe₃. Adv Energy Mater. 2021;11(42):2100661.

[24] Xu S, Zhou H, Sun Z, Xie J. Formation of an fcc phase through a bcc metastable state in crystallization of charged colloidal particles. Phys Rev E. 2010;82(1):010401.

[25] Lyu T, Li X, Yang Q, et al. Stepwise Ge vacancy manipulation enhances the thermoelectric performance of cubic GeSe. Chem Eng J. 2022;442:136332.

[26] Li X, Liang Z, Li J, et al. Crystal symmetry enables high thermoelectric performance of rhombohedral GeSe(MnCdTe₂)_x. Nano Energy. 2022;100:107434.

[27] Wang Z, Wu H, Zhang B, et al. Phase modulation enabled high thermoelectric performance in polycrystalline GeSe_0.75Te_0.25. Adv Funct Mater. 2022;32(26):2111238.

[28] Sarkar D, Roychowdhury S, Arora R, et al. Metavalent bonding in GeSe leads to high thermoelectric performance. Angew Chem Int Ed. 2021;60(18):10350-10358.

[29] Yan M, Geng H, Jiang P, Bao X. Glass-like electronic and thermal transport in crystalline cubic germanium selenide. J Energy Chem. 2020;45:83-90.

[30] Sist M, Gatti C, Nørby P, et al. High-temperature crystal structure and chemical bonding in thermoelectric germanium selenide (GeSe). Chem Eur J. 2017;23(28):6888-6895.

[31] Huang Z, Miller SA, Ge B, et al. High thermoelectric performance of new rhombohedral phase of GeSe stabilized through alloying with AgSbSe₂. Angew Chem Int Ed. 2017;56(45):14113-14118.

[32] Lencer D, Salinga M, Grabowski B, Hickel T, Neugebauer J, Wuttig M. A map for phase-change materials. Nat Mater. 2008;7(12):972-977.

[33] Yu Y, Zhou C, Ghosh T, et al. Doping by design: enhanced thermoelectric performance of GeSe alloys through metavalent bonding. Adv Mater. 2023;35(19):2300893.

[34] Hu L, Duan B, Lyu T, et al. In situ design of high-performance dual-phase GeSe thermoelectrics by tailoring chemical bonds. Adv Funct Mater. 2023;33(17):2214854.

[35] Lewis GN. The atom and the molecule. J Am Chem Soc. 1916;38(4):762-785.

[36] Wuttig M, Schön C-F, Lötfering J, Golub P, Gatti C, Raty JY. Revisiting the nature of chemical bonding in chalcogenides to explain and design their properties. Adv Mater. 2023;35(20):2208485.

[37] Yu Y, Cagnoni M, Cojocaru-Mirédin O, Wuttig M. Chalcogenide thermoelectrics empowered by an unconventional bonding mechanism. Adv Funct Mater. 2020;30(8):1904862.

[38] Guarneri L, Jakobs S, von Hoegen A, et al. Metavalent bonding in crystalline solids: how does it collapse? Adv Mater. 2021;33(39):2102356.

[39] Duan B, Zhang Y, Yang Q, et al. The role of cation vacancies in GeSe: stabilizing high-symmetric phase structure and enhancing thermoelectric performance. Adv Energy Sustain Res. 2022;3(11):2200124.

[40] Xu X, Xie L, Lou Q, Wu D, He J. Boosting the thermoelectric performance of pseudo-layered Sb₂Te₃(GeTe)_n via vacancy engineering. Adv Sci. 2018;5(12):1801514.

[41] Zhong J, Liang G, Cheng J, et al. Entropy engineering enhances the thermoelectric performance and microhardness of (GeTe)_1–x(AgSb_0.5Bi_0.5Te₂)_x. Sci China Mater. 2023;66(2):696-706.

[42] Xu M, Jakobs S, Mazzarello R, et al. Impact of pressure on the resonant bonding in chalcogenides. J Phys Chem C. 2017;121(45):25447-25454.

[43] Raty J-Y, Wuttig M. The interplay between peierls distortions and metavalent bonding in IV–VI compounds: comparing GeTe with related monochalcogenides. J Phys D Appl Phys. 2020;53(23):234002.

[44] Wang Z, Wu H, Xi M, et al. Structure-dependent thermoelectric properties of GeSe_1–xTe_x (0 ≤ x ≤ 0.5). ACS Appl Mater Interfaces. 2020;12(37):41381-41389.

[45] Littlewood PB. The crystal structure of IV-VI compounds. I. Classification and description. J Phys C Solid State Phys. 1980;13(26):4855-4873.

[46] Arora R, Waghmare UV, Rao CNR. Metavalent bonding origins of unusual properties of group IV chalcogenides. Adv Mater. 2023;35(7):2208724.

[47] Cagnoni M, Führen D, Wuttig M. Thermoelectric performance of IV–VI compounds with octahedral-like coordination: a chemical-bonding perspective. Adv Mater. 2018;30(33):1801787.

[48] Küpers M, Konze PM, Maintz S, et al. Unexpected Ge–Ge contacts in the two-dimensional Ge₄Se₃Te phase and analysis of their chemical cause with the density of energy (DOE) function. Angew Chem Int Ed. 2017;56(34):10204-10208.

[49] Yao Z, Li W, Tang J, et al. Solute manipulation enabled band and defect engineering for thermoelectric enhancements of SnTe. InfoMat. 2019;1(4):571-581.

[50] Zhang X, Shen J, Lin S, et al. Thermoelectric properties of GeSe. J Materiomics. 2016;2(4):331-337.

[51] Hong M, Wang Y, Feng T, et al. Strong phonon–phonon interactions securing extraordinary thermoelectric Ge_1–xSb_xTe with Zn-alloying-induced band alignment. J Am Chem Soc. 2019;141(4):1742-1748.

[52] Su D, Cheng J, Li S, et al. Inhibiting the bipolar effect via band gap engineering to improve the thermoelectric performance in n-type Bi_2-xSb_xTe₃ for solid-state refrigeration. J Mater Sci Technol. 2023;138:50-58.

[53] Hu L, Meng F, Zhou Y, et al. Leveraging deep levels in narrow bandgap Bi_0.5Sb_1.5Te₃ for record-high zT_ave near room temperature. Adv Funct Mater. 2020;30(45):2005202.

[54] Moshwan R, Yang L, Zou J, Chen Z-G. Eco-friendly SnTe thermoelectric materials: progress and future challenges. Adv Funct Mater. 2017;27(43):1703278.

[55] May AF, Toberer ES, Saramat A, Snyder GJ. Characterization and analysis of thermoelectric transport in n-type Ba₈Ga_16-xGe_30+x. Phys Rev B Condens Matter Mater Phys. 2009;80(12):125205.

[56] Yan M, Tan X, Huang Z, Liu G, Jiang P, Bao X. Synergetic optimization of electronic and thermal transport for high-performance thermoelectric GeSe–AgSbTe₂ alloy. J Mater Chem A. 2018;6(18):8215-8220.

[57] Yao W, Zhang Y, Lyu T, et al. Two-step phase manipulation by tailoring chemical bonds results in high-performance GeSe thermoelectrics. Innovation. 2023;4(6):100522.

[58] Lee S, Esfarjani K, Luo T, Zhou J, Tian Z, Chen G. Resonant bonding leads to low lattice thermal conductivity. Nat Commun. 2014;5(1):3525.

[59] Zhu J, Xie L, Ti Z, et al. Computational understanding and prediction of 8-electron half-heusler compounds with unusual suppressed phonon conduction. Appl Phys Rev. 2023;10(3):031405.

[60] Han S, Dai S, Ma J, et al. Strong phonon softening and avoided crossing in aliovalence-doped heavy-band thermoelectrics. Nat Phys. 2023;19(11):1649-1657.

[61] Chen Z, Zhang X, Lin S, Chen L, Pei Y. Rationalizing phonon dispersion for lattice thermal conductivity of solids. Natl Sci Rev. 2018;5(6):888-894.

[62] Wang X, Yao H, Yin L, et al. Band modulation and strain fluctuation for realizing high average zT in GeTe. Adv Energy Mater. 2022;12(26):2201043.

RIGHTS & PERMISSIONS

2024 The Authors. Interdisciplinary Materials published by Wuhan University of Technology and John Wiley & Sons Australia, Ltd.